RFR: 8254995: [x86] ControlWord::print(), rc/pc variables might not be initialized [v2]

[Aleksey Shipilev]

> Static analyzers complain that in `ControlWord::print()`, `rc`/`pc` variables might not be initialized. This never
> happens in practice, because `rounding_control()` and `precision_control()` return the good values. We can make it
> cleaner to silence the compiler.  Testing:
>   - [x] Linux x86_64 tier1

Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:

  Use fatal(), initialize to NULL and add comments

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/731/files
  - new: https://git.openjdk.java.net/jdk/pull/731/files/dc6c1187..eb1705ac

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=731&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=731&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/731.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/731/head:pull/731

PR: https://git.openjdk.java.net/jdk/pull/731